OLYMPIA – State investigators have determined that an excessive buildup of mussels and other marine organisms on nets – caused by Cooke Aquaculture's failure to properly clean them – led to the August 19 collapse of the company's net pen at Cypress Island.

An investigative report – authored by the departments of Natural Resources (DNR), Ecology, and Fish and Wildlife (WDFW) – found that 110 tons of mussels and plants had accumulated on the nets before the incident. The report was released today at a news conference in Olympia.

The investigation determined that tidal currents pushing against the tremendous mass of organisms on the nets overwhelmed the pen's mooring system and crushed the pen.

Extensive corrosion of the net pen structure also contributed to the collapse.

In addition, the agencies identified shortcomings in engineering practices that likely contributed to the failure.

Properly designed and maintained net pens would have withstood the tidal currents of August 19.

"The collapse was not the result of natural causes," said Hilary Franz, Commissioner of Public Lands. "Cooke's disregard caused this disaster and recklessly put our state's aquatic ecosystem at risk."

"The results of our investigative report clearly show a significant violation of Washington's water quality laws," said Ecology Director Maia Bellon. "Cooke Aquaculture could have prevented this failure."

"Cooke made this situation even more difficult by under-reporting the number of fish that escaped during the net-pen collapse, and over-reporting the number it recovered afterward," said Amy Windrope, WDFW's north Puget Sound regional director.

Growth of mussels and other marine organisms on nets – called "biofouling" – is documented in state agency videos that show a "rain" of mussels falling off nets as debris from the collapse was removed.

The severe biofouling produced 110 tons of material – an average of 11 tons per net.

Cooke's Failure to Act

Prior to the collapse, Cooke was aware of both the excessive biofouling and the poor condition of the facility.

The report details how Cooke didn't follow its net pen cleaning schedule when broken net washers were not repaired or replaced. This allowed mussels to accumulate on the nets, which increased the drag from currents and added pressure to the structure.

Cooke also failed to take necessary precautions after the net pens were moved out of position in July when strong currents broke ten mooring points.

Cooke documents show that after the July incident, the company had serious concerns about the facility. An internal company email stated, "We almost lost the farm."

Nevertheless, after the July incident, Cooke considered, but did not:

Replace the biofouled nets,

Begin their salmon harvest early, or

Increase monitoring of the net pens and have a tug on standby when strong currents were again expected on August 19.

The report notes that state agencies did not investigate the July incident because they received incomplete and misleading information from Cooke.

More Salmon Escaped Than Cooke Reported

The report also found that Cooke misrepresented the number of fish it harvested when the pen collapsed. According to the report:

The investigation concluded that Cooke could only have extracted between 42,000 and 62,000 fish.

Therefore, between 243,000 and 263,000 fish actually escaped. Previous estimates, based on Cooke's reports, put the number of escaped fish at 160,000.

Of the escaped fish, 57,000 have been caught.

Between 186,000 and 206,000 Atlantic salmon remain unaccounted for.

The report concludes that monitoring through the winter and next fall's salmon run season will be critical to knowing if any escaped Atlantic salmon remain in Washington's waters and if they are reproducing.

Commissioner Franz is currently reviewing the report and will make an announcement about the future of the Cypress Island facility in the coming days.

In December, DNR terminated Cooke's lease of state aquatic lands in Port Angeles, citing a failure to maintain the facility in a safe condition.

Ecology intends to take enforcement action against Cooke Aquaculture for violating Washington's water quality laws.

This multi-agency report included information collected during and after the incident, interviews with Cooke staff, and an engineering review of the failure.